Device for heating the internal mercury vapor high vacuum pumps of rectifiers



w. DALLENBACH EVICE FOR HEATING THE INTERNALMERCURY D 1,834,146

1 1931- VAPOR HIGH VACUUM PUMPS OF ,REOTIFIERS Filed July 21, 1924 33L.wad/28mm Patented Dec. 1, 1931 UNITED STATES PATENT OFFICE WALTERDALLENBACH, OF ZURICH, SWITZERLAND, ASSIGNOR TO AKTIENGESEIL- SCHAITBROWN, .BOVERI AND CIR, OF BADEN', SWITZERLAND DEVICE FOR HEATING THEINTERNAL MERCURY VAPOR, HIGH VACUUM" PUMPS OF RECTIFIEBS Applicationfiled July 21, 1524, Serial'No. 727,398, and in Germany July 30, 1923.

It is known in rectifiers to build the mercury vapor high-vacuum pumpinto the-rectifier vessel itself. It is also known, 1n the case ofmercury vapor pumps that are not 5 built-in, to pass the excitingcurrentv of the rectifier in the form of a heating current through theheating winding of the pump. According to the invention. the heat-ingwmding in built-in pumps can be dispensed with by using at least oneexciting anode as the.

heating body for the pump. The heat liberated in the voltage drop of theanode serves to evaporate the mercury of the pump.

The drawing illustrates diagrammatically a constructional example of theinvention. Ihe cooling dome b of the rectifier a, at the uppermost partof which is provided the connection i for the preliminary vacuum pump,serves at the same time as a condensing chamber for the mercury of thehigh-vacuum pump, which is situated in the vessel 0. This latter isheated by means of the exciting anode d, which is constructed in theform of a plate.

' In order to enable more energy to be liberated at this heating anodethan at the other exciting anodes (not shown), the secondary side of theexciting transformer e is made asymmetrical. Moreover, the phase voltagein the heating anode phase is greater than in the other exciting phases.In addition to this, resistances and reactances f, g are dis-' posed asshown between the exciting transformere and the anodes, theseresistances being chosen smaller in the heating anode phase f than inthe other exciting phases g. The neutral point of the excitingtransform- 40 er e is directly connected to the cathode kof therectifier, but could also be connected therewith through a choking coil.

Several exciting anodes could also be used to heat the high vacuum pump.The ignition anode k, which can also be connected to the excitingtransformer, cannot of course be used to heat the pump 0.

What I claim is 1. In a mercury vapor discharge device, an enclosingvessel, a plurality of electrodes for maintaining a mercury vapordischarge in said vessel, one of said electrodes being a mercury cathodesaid vessel having an exhaust opening, and a mercury vapor condensationpump consisting in part of a portion of said vessel and being incommunication therewith for expelling gases through said opening, theenergy for operating said mercury vapor pump being part of the energydissipated in the discharge in said vessel.

2. In an electric vapor rectifier, an enclosing casing, amercury cathodewithin said casing, anode means operating with said cathode to maintaina discharge within said casing, said casing having an exhaust openmg forevacuating the same, and means for utlhzlng the energy dissipated atsaid anode means -for generating a vapor blast evacuating said casingthrough said opening.

3. In an electric current rectifier of the arc type, a casing having anexhaust port, anodes within said casing, a mercury cathode within saidcasing and cooperating with said anodes to maintain an arc therebetween,and vapor discharging means disposed within and cooperating with saidcasing to evacuate the same, the energy dissipated at one of said anodesbeing used for generating the vapor discharged from said means.

4. In an electric current rectifier of the arc type, a casing having anexhaust port, an anode of plate-shape within said casing, a mercurycathode within said casing and cooperating with said anode to maintainan arc vtherebetween, and vapor discharging means disposed within andcooperating with said casing to evacuate the same, the energy dissipatedat said plate-shaped anode being used for generating the vapordischarged from said means.

5. In an electric current rectifier of the arc type, a casing havin anexhaust port, a mercury cathode in sai casing, a plurality of excitinganodes for maintaining the mercury of said cathode in ionized condition,vapor discharging means disposed within and cooperating with said casingfor evacuating the same, the energy dissipated at one of said excitinganodes being supplied to said means for producing a vapor blasttherefrom, and means for so distributing the energy supplied to suchexciting anodes as to dissipate a greater amount of energy at said anodeproviding the energy for said vapor discharging means than at the othersof said anodes.

In testimony whereof I have signed my name to this specification.

WALTER DALLENBAOH.

